To investigate the efficacy of Mudan Particles combined with mecobalamine in the treatment of painful diabetic peripheral neuropathy (PDPN). Methods: One hundred patients with PDPN were randomly divided into treatment group (n=50) and the control group (n=50).Based on the basic control of blood glucose, the control group were treated with mecobalamine; the treatment group were treated with Mudan Particles in addition to the control group.Observe the treatment effect and the peroneal nerve conduction velocity of two groups before and after treatment.Results: TCSS of the two groups improved after treatment (P<0.05, but the treatment group improved rather significantly. For pain, the total effective rate of the treatment group (86％) was higher than that of the control group.After treatment, MCV and SCV of common personal nerve of the treatment group were faster than those of the control group(P<0.05).Conclusion: Mudan Particles combined with mecobalamine have a good effect on nerve conduction velocity improvement and pain relief in the treatment of PDPN, and have no significant adverse reaction.